微囊藻毒素测定中产生的干扰及排除

采用固相萃取-高效液相色谱法定性、定量测定水中微囊藻毒素,对水样富集管(观赏鱼用氧气塑料管、橡胶管、医用乳胶管和硅胶管)、塑料材质(聚丙烯离心管等)、针式过滤器(水系、有机系针式过滤器)产生的干扰和吸附现象进行了深入探索.结果表明,观赏鱼用氧气塑料管对微囊藻毒索测定会产生严重的正干扰,在流动相甲醇:磷酸盐缓冲溶液(体积比)为50:50时,干扰得以排除;聚丙烯离心管在微囊藻毒素投加量较低时,对微囊藻毒索吸附率较高,造成回收率偏低;不同的针式过滤器对溶解在不同体积分数的甲醇溶液中的微囊藻毒素有明显不同的吸附能力.     

Aviation and global climate change in the 21st century

Aviation emissions contribute to the radiative forcing (RF) of climate. Of importance are emissions of carbon dioxide (CO₂), nitrogen oxides (NO_x), aerosols and their precursors (soot and sulphate), and increased cloudiness in the form of persistent linear contrails and induced-cirrus cloudiness. The recent Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) quantified aviation's RF contribution for 2005 based upon 2000 operations data. Aviation has grown strongly over the past years, despite world-changing events in the early 2000s; the average annual passenger traffic growth rate was 5.3% yr^?1 between 2000 and 2007, resulting in an increase of passenger traffic of 38%. Presented here are updated values of aviation RF for 2005 based upon new operations data that show an increase in traffic of 22.5%, fuel use of 8.4% and total aviation RF of 14% (excluding induced-cirrus enhancement) over the period 2000–2005. The lack of physical process models and adequate observational data for aviation-induced cirrus effects limit confidence in quantifying their RF contribution. Total aviation RF (excluding induced cirrus) in 2005 was ～55 mW m^?2 (23–87 mW m^?2, 90% likelihood range), which was 3.5% (range 1.3–10%, 90% likelihood range) of total anthropogenic forcing. Including estimates for aviation-induced cirrus RF increases the total aviation RF in 2005–78 mW m^?2 (38–139 mW m^?2, 90% likelihood range), which represents 4.9% of total anthropogenic forcing (2–14%, 90% likelihood range). Future scenarios of aviation emissions for 2050 that are consistent with IPCC SRES A1 and B2 scenario assumptions have been presented that show an increase of fuel usage by factors of 2.7–3.9 over 2000. Simplified calculations of total aviation RF in 2050 indicate increases by factors of 3.0–4.0 over the 2000 value, representing 4–4.7% of total RF (excluding induced cirrus). An examination of a range of future technological options shows that substantive reductions in aviation fuel usage are possible only with the introduction of radical technologies. Incorporation of aviation into an emissions trading system offers the potential for overall (i.e., beyond the aviation sector) CO₂ emissions reductions. Proposals exist for introduction of such a system at a European level, but no agreement has been reached at a global level.     

一体化A/O工艺碳氮比对脱氮除碳的影响

依据好氧硝化和缺氧反硝化生物脱氮除碳工艺原理,设计了一体化生物膜法A/O反应器,并将其应用于生活污水处理,取得了理想的处理效果。实验结果表明,水力停留时间HRT＝12 h,COD进水浓度处于150～500 mg/L范围内,COD的去除率均在90%以上,且出水均在40 mg/L以下;当C/N比为8.5以下时,NH₃-N去除率高于90%,其出水浓度小于5 mg/L;当C/N比为7.5左右时,具有较高的总氮脱除效果,TN去除率可达到70%。     

锰矿尾渣改性壳聚糖对Pb2+的吸附

将工业废弃物锰矿尾渣与壳聚糖混合制得一种高效吸附剂,并应用扫描电镜、X射线衍射对其结构进行了表征。采用正交表设计试验,分别考察了pH值、吸附时间、温度、复合吸附剂的投加量等4个影响因素对Pb²⁺吸附的影响,最佳吸附条件为：pH值为7,吸附时间为40 min,温度为20℃,复合吸附剂的投加量为0.10 g。处理后的水符合国家污水综合排放标准（GB8978-1996）中的一级标准。复合吸附剂对Pb2+的吸附符合Langmuir和Freundlich吸附等温方程。     

微波辅助白腐真菌煤炭脱硫试验研究

将微波技术与生物技术相结合用于煤炭脱硫,采用微波功率1 000 W、辐照时间80 s对煤样进行辐照处理后,考察了初始pH值、煤粉粒径和煤浆浓度对微波辅助白腐真菌脱硫效果的影响,以及脱硫过程中硫化物的转化规律。研究结果表明,微波辐照作用能够缩短脱硫周期,提高有机硫的脱除率。在初始pH值为4.5,煤粉粒径为80～120目,煤浆浓度为10%,浸出时间为3 d的条件下,煤中的全硫、无机硫和有机硫脱除率分别达到52.06%、51.61%和54.22%。     

宜宾饮食文化资源的旅游开发研究

饮食文化对旅游业发展有着不可忽视的促进功能,饮食文化旅游资源的开发已越来越被旅游业所重视。宜宾饮食文化源远流长,具有浓郁的地方特色,但对宜宾饮食文化资源的旅游开发尚处于起步阶段。在分析宜宾饮食文化资源旅游开发现状的基础上,就如何把宜宾饮食文化资源的开发与旅游业的发展相结合,做大做强宜宾旅游美食文化产业提出了一些开发对策和建议。     

Characteristics of ozone pollution and the sensitivity to precursors during early summer in central plain, China

In this study, we conducted an observation experiment from May 1 to June 30, 2018 in Zhengzhou, a major city in central China, where ground ozone (O₃) pollution has become serious in recent years. The concentrations of O₃ and its precursors, as well as H₂O₂ and meteorological data were obtained from the urban site (Yanchang, YC), suburban (Zhengzhou University, ZZU) and background sites (Ganglishuiku, GLSK). Result showed that the rates of O₃ concentration exceeded Chinese National Air Quality Standard Grade II (93.3 ppbv) were 59.0%, 52.5%, and 55.7% at the above three sites with good consistency, respectively, indicating that O₃ pollution is a regional problem in Zhengzhou. The daily peak O₃ appeared at 15:00–16:00, which was opposite to VOCs, NO_x, and CO and consistent with H₂O₂. The exhaustive statistical analysis of meteorological factors and chemical effects on O₃ formation at YC was advanced. The high concentration of precursors, high temperature, low relative humidity, and moderately high wind speed together with the wind direction dominated by south and southeast wind contribute to urban O₃ episodes in Zhengzhou. O₃ formation analysis showed that reactive alkenes such as isoprene and cis-2-butene contributed most to O₃ formation. The VOCs/NO_x ratio and smog production model were used to determine O₃-VOC-NO_x sensitivity. The O₃ formation in Zhengzhou during early summer was mainly under VOC-limited and transition regions alternately, which implies that the simultaneous emission reduction of alkenes and NO_x is effective in reducing O₃ pollution in Zhengzhou.     

近岸海域水色算法真实性检验的不同叶绿素a测试方法换算模型

现场叶绿素a浓度是卫星水色遥感算法真实性检验的重要依据.测试方法不同,对遥感反演的叶绿素浓度对比有较大的影响.本文依据海洋监测规范和NASA的海洋光学观测规范采用三色光分光光度法、荧光光度法和HPLC法对辽东湾、大连湾水样的同步分析,建立了分光法与荧光法、分光法与HPLC法、荧光法与HPLC法得到的叶绿素a浓度换算模型,各相关系数均高于0.8,显示了良好的一致性.     

我国农田土壤碳氮耦合特征的区域差异

利用中国第2次土壤普查数据,分析了稻作和旱作方式下农田耕层土壤有机碳和全氮特征及其区域差异。结果表明,水田土壤有机碳和全氮含量分别为旱地的147.8%和145.5%,但水田碳氮含量的区域变异低于旱地。全国水田和旱地土壤有机碳氮比值分别为10.8和9.9,各区域水田土壤碳氮比值普遍高于旱地,其中东北水田最高,而华东旱地和西北旱地最低。旱地碳氮比值的区域变异显著,水田则不显著。农田耕层土壤有机碳和全氮含量呈显著正相关,除华北地区外,各区域无论水田还是旱地其碳氮含量之间相关系数都超过0.8,达极显著水平。由此可见,我国农田耕层土壤有机碳和全氮含量之间存在显著耦合关系,而且不同利用方式和区域之间差异显著;相同氮水平下,水田土壤可能储存更多的有机碳。     

不同温度条件下呋喃丹对赤子爱胜蚓体内蛋白含量以及SOD和AChE活性的影响

采用滤纸法研究不同温度下呋喃丹对赤子爱胜蚓(Eisenia foetida)死亡率、体内蛋白含量以及超氧化物歧化酶(SOD)和乙酰胆碱酯酶(AChE)活性的影响.研究发现,10 ℃下,蚯蚓体内蛋白含量在30 mg·L-1呋喃丹处理时略有升高,而后随时间和浓度的升高,蛋白含量则随之降低;各浓度处理组的SOD活性值基本上高于对照组,48和72 h的SOD活性比24 h时平均提高220%和148%.时间和浓度对蛋白含量和SOD活性的影响达到极显著(P＜0.01).而在20 ℃下,蚯蚓体内蛋白含量和SOD活性变化规律均不明显,表明当温度升高时,呋喃丹对蚯蚓生理生化指标的作用更趋于复杂.在2种温度下,农药对蚯蚓体内AChE活性都具有明显抑制作用,AChE活性在处理时段内的最高降低率为90%.结果表明:温度对蚯蚓死亡率、蛋白含量以及SOD和AChE活性影响显著,AChE可以作为一个稳定的生物监测指标用于评价农药对土壤环境的污染影响.